The Ganges River, known as Ganga, holds profound cultural and ecological significance for India, revered as a sacred mother goddess and a lifeline for millions. It originates in the Himalayas and flows across northern India and Bangladesh before emptying into the Bay of Bengal. The river faces severe pollution, threatening both human health and the environment it sustains. This degradation stems from human activities along its densely populated basin.
Untreated Domestic Wastewater
A primary contributor to the Ganges’ pollution is the discharge of untreated domestic wastewater from the numerous cities and towns lining its banks. The Gangetic plain is one of the most densely populated river basins globally, supporting over 450 million people. Rapid urbanization has outpaced the development of sufficient wastewater treatment infrastructure, leading to vast quantities of sewage directly entering the river daily. More than 3 billion liters of untreated sewage are released into the river each day.
This influx of human waste introduces a high organic load and harmful pathogens, including fecal coliform bacteria, making the water unsafe for human contact and consumption. Fecal coliform levels in parts of the river have been found to be extremely high, sometimes exceeding 100,000,000 MPN per 100 mL, far above the bathing limit of 2,500 MPN per 100 mL. This bacterial contamination poses substantial health risks, including waterborne diseases like gastrointestinal illnesses, typhoid, and hepatitis A for those relying on the river. Even where treatment plants exist, many are either non-operational or inefficient, with only about 37% of generated sewage being treated.
Industrial Discharges
Industrial activities along the Ganges River also contribute significantly to its pollution, discharging toxic effluents directly into the waterway. Cities like Kanpur, Prayagraj, Varanasi, and Patna host numerous industries, including tanneries, chemical plants, textile mills, distilleries, and slaughterhouses. These facilities release untreated or partially treated waste containing hazardous substances.
Pollutants from these industries include heavy metals such as chromium, lead, mercury, cadmium, and arsenic, alongside toxic chemicals and dyes. For instance, the leather industry in Kanpur, with hundreds of tanneries, is a major source of chromium contamination. Industrial effluents, while accounting for a smaller volume (around 12%) of the total waste, are concerning due to their toxicity and persistence in the environment. These substances impact aquatic life and accumulate in the food chain, posing long-term health hazards for humans who consume contaminated fish or vegetables irrigated with river water.
Agricultural Contamination
Agricultural practices across the vast Gangetic plain add to the river’s pollution through chemical runoff. Modern farming methods involve extensive use of chemical fertilizers and pesticides. Runoff from these agricultural fields carries these chemicals into the river system.
The influx of chemical fertilizers introduces excess nutrients into the river, a process known as eutrophication. This nutrient enrichment can lead to excessive growth of algae and aquatic plants, which then deplete oxygen levels when they decompose, harming fish and other aquatic organisms. Pesticides, including persistent compounds like DDT, which can still be found, also contaminate the water, affecting aquatic biodiversity and potentially entering the human food chain. An estimated 6 million tons of fertilizers and 9,000 tons of pesticides are used daily in agriculture within the Ganga basin, contributing to this runoff.
Cultural Practices and Solid Waste
Beyond industrial and domestic sources, cultural practices and solid waste dumping contribute to the Ganges River’s pollution. Traditional and religious customs, interwoven with the river’s spiritual significance, add to the pollution burden. Practices like idol immersion, floral offerings, and other ceremonial materials introduce organic and non-biodegradable waste into the water.
Idols, often made from plaster of Paris and painted with synthetic colors containing heavy metals like lead, cadmium, copper, and mercury, do not readily dissolve and release toxic elements upon immersion. Additionally, the disposal of ash remains from cremations and, in some cases, uncremated bodies, contributes to organic pollution and bacterial load. Compounding these issues is the problem of general solid waste dumping, including plastics and other non-biodegradable items, by local populations and pilgrims. These materials obstruct water flow, harm aquatic life through ingestion or entanglement, and further degrade the river’s water quality and ecosystem health.